Multiphase trip indicator means with common reset



Nov. 8, 1955 T. G. BANK arm.

MULTIPHASE TRIP INDICATOR MEANS WITH COMMON RESET Filed Sept. 22, 1954 5Sheets-Sheet l 3 3 .IDIB fi 3 3 3 {0- L 1 L n 4, n M n u u n m M 4 a I p5 aw i 0 Z flu Z W m 0 m WW Z ffi a a fl k v J o fiz ,w W 6 0 J 5 L i aM 3 3 7 J m w w i w, 7/ 5 r 7, 7 7,; 0 1 M a o J 4, 1 5 /4 Z///avwz-vxkona ewrl. f5. @30MX4 f? tom M. 5M 1.

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MULTIPHASE TRIP INDICATOR MEANS WITH COMMON RESET Filed Sept. 22, 1954 3Sheets-Sheet 2 [Iii Iii}: ):::::3:3

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v- 8, 1955 T. G. BANK ETAL 2,723,326

MULTIPHASE TRIP INDICATQR MEANS WITH COMMON RESET 7 7 Filed Sept. 22,1954 3 Sheets-Sheet 3 United States Patent MULTIPHASE TRIP INDICATORMEANS WITH COMMON RESET Thor G. Bank and Stanton H. Telantler,Milwaukee, Wis., assignors to Allis-Chalmers Manufacturing Company, WestAllis, Wis.

This invention relates generally to a multiphase electricalinstallation, in which each phase is protected by a circuit breaker.

More particularly the invention is directed to a trip indicator meansfor identifying one or more phases of the multiphase installation, theindicator means being provided with a common reset for all phases.

The invention permits one or more phases to trip in response toelectrical overload conditions and to be indicated without affecting thenontripped phases. A trip shaft, common to all of the phases in themultiphase installation, is provided. Each phase has an indicator meansfor visually identifying a trip and a nontrip phase. Each of theindicator means includes a collar which is journaled in alignment withcollars of the other indicator means, in a common support. The collarsall cooperate to journal a trip shaft in alignment and common to all ofthe phases. Each of the collars is provided with a recess at one endthereof and carries an indicator aflixed to the collar for rotationtherewith. The indicator is provided with a latched portion forcooperation with a latch. The latch cooperates with the latch portionsto hold the indicator in a nontrip position. The latchis connected tomeans which are responsive to operation of the tripping mechanism of oneof the breakers and disengages the latch from the latched portion todrop the indicator in response to the operation of these means.

A limit pin is mounted on the shaft and extends into the recess of eachof the collars. The limit pin is mounted in the recess with a clearancefor turning the shaft with lost motion in response to engagement of awall of the recess with the pin. In addition, mounted on the collar is atorsion resilient means which maintains tension on the collar causingthe latched portion of the priate linkages which causes the shaft to berotated in a direction opposed to that of tripping. The reset buttonalso acts as a breaker'tripped indicator by popping out when the breakeris tripped as a result of overload conditions in the protectedinstallation.

An object of the present invention is to provide an improved multiphasetrip indicator means in which the indicators operate independently ofeach other, to indicate the tripped and nontripped phases.

Another object of this invention is to provide arelatively simple andfoolproof indicating means for visually identifying a tripped and anontripped phase in a multiphase installation.

Another object of this invention is to provide indicator means which arereadily adaptable to be combined with an alarm switch which is operatedby action of the indicator means upon tripping of any of one or more ofthe phases of the multiphase installation.

Another object of this invention is to provide an indi- .cating means ina multiphase installation which includes a lockout device combined withthe indicator means to lock the breaker trip shaft in a trippedposition, to prevent personnel from accidently closing the circuitbreaker until circuit faults have been eliminated.

Other objects and advantages than those set forth will be apparent fromthe following description when read in connection with the accompanyingdrawings, in which:

Fig. l is a side view in elevation of a circuit breaker employed in aphase of the multiphase protected installation embodying the invention,portions of the breaker are broken away to show greater details;

Fig. 2 is an enlarged fragmentary plan view showing the trip relays andportions of a three phase protected installation embodying theinvention;

Fig. 3 is an enlarged fragmental view of the collar and trip shaftassembly;

Fig. 4 is a view taken along line IVIV of Fig. 3;

Fig. 5 is an enlarged view in elevation of the tripping mechanism andthe indicator means shown in a nontripped position; and

Fig. 6 is a view of the same structure shown in Fig. 5, however, shownin a tripped position.

Structure embodying the invention is shown in Figs. 1 through 6. Themultiphase protected installation to which the invention relates is athree phase protected installation in which each individual phaseemploys a circuit breaker 10 such as shown in Fig. 1. Accordingly, thecomplete structure and operation of only one of the circuit breakers isshown and described, while the trip relay 40 of each circuit breaker ofthe three phase installation is shown in Fig. 2.

Referring more particularly to the drawing, Fig. 1 shows a circuitbreaker 10 for protecting a circuit (not shown). Breaker 10 may beconnected in series with the circuit and must therefore be made largeenough to interrupt the maximum currents to be carried by such circuit.Circuit breaker 10 and its component parts are mounted on a back panel11.

Copper bar studs 12, 16 are mounted in and project through the backpanel and may be made of any known good conductive material but arepreferably made of copper. Mounted on one extremity of bar studs 12, 16are primary fingers 13 which connect breaker 10 with the circuit. Upperand lower contact blocks 14, 15 are of like construction, with the lowerblock 15 being mounted on back panel 11 inaposition as viewed in Fig. 1of the drawing, to the position of upper contact block 14. The bar stud12 is firmly aflixed to upper contact block 14 by means known in the artwhich will produce a low resistance joint, preferably being brazed orbolted to block 14. Bar stud 16 is afiixed in like manner to a trip coil21.

A main finger 18 is fulcrumly carried by the contact block 14 to permitlimited arcuate movement of main finger 18 relative to block 14. Aspring 19 is positioned intermediate main finger 18 and block 14 toproduce a permanent closing bias for main finger 18. A contact arm 20 ispivotally mounted on contact block 15 and mechanically and electricallyengages main finger 18 A trip coil 21 is connected to contact block 15at one of the coil ends, and the other end thereof is connected to thebar stud 16, which is'connected with the primary fingers 13 mountedthereon, completing the series circuit through the breaker 10.

This provides a current path designated as the primary current pathwhich carries substantially full circuit current, which current isconducted through the breaker 10 from primary fingers 13 to bar stud 12to contact block 15 and through the trip coil 21, the bar stud 16 andthe primary fingers 13, thus completing the primary current path throughthe breaker 10.

A secondary or arcing current path includes an arcing contact arm 24which is pivotally carried by and mounted on contact arm 20 at a pivot25. Arcing contact arm 24 may be extruded from a good conductingmaterial, such as copper. An arcing contact 26 is brazed to arcingcontact arm 24. The arcing contact 26 being preferably made of silvertungsten alloy must be capable of withstanding high arcing temperaturesand currents. A complementary arcing contact 27, which extends into anarc runner 28 is similar in material to arcing contact 26, and isaffixed to and carried by contact block 14.

When breaker is in a closed position (as shown in Fig. l) arcing contact26 of arcing contact arm 24 is biased by a spring 29 carried by contactarm 20, against arcing contact 27 carried by contact block 14. Thecontact arm which is integral at its top part 33 is cut apart at itsbottom part 34 forming two legs physically and electrically insulatedfrom each other by insulating washer 35. The secondary or arcing currentpath receives its current from contact block 14 through arcing contacts26, 27 flowing down arcing contact arm 24 through the pivot and up theleft hand leg of contact arm 20 from the lower part 34 to the upper part33 thence down the right hand leg contact arm 20 to contact block 15,aiding the primary current. This secondary current path aids to holdarcing contact arm 24 and contact arm 29 in a closed position because ofthe electromagnetic force created by the loop type current path.

The spring 19 provided intermediate the main finger and the contactblock biases main finger 18 against contact arm 28 when breaker 10 isclosed. Another spring 29 exerts force on arcing contact arm 24 to biasarcing contacts 26, 27 in a closed position. An insulating disk 36 isprovided intermediate spring 29 and arcing contact arm 24 toelectrically insulate one from the other. Another such insulating disk37 is provided on the arcing arm 24 opposing disk 36 to cushion andinsulate the opening of contact arm 20.

The series trip coil 21 is shown as part of an overcurrent trip relay 40which in turn is part of a breaker tripping mechanism 41 adapted to makeand break main finger 18 and contact arm 20. Trip coil 21 is illustratedas series connected with the primary circuit but may be parallelconnected with the circuit to provide potential responsiveness forbreaker operation, as is well known in the art. Trip relay 40 hasamagnetizable core 42 and trip coil 21 mounted thereon and magneticallycoupled therewith. An armature 45, part of relay 40, is pivotallycarried by core 42 at pivot 46 and is responsive to electrical changesin the circuit. The armature is limited in movement to its open positionby a stop .pin 47 carried by breaker 10.

Armature 45 is biased by .a spring 38 against pickup. One end ofspring38 engages a knob 39 on the armature 45 and the other end thereofis carried by a pickup adjusting structure ,43. The pickup adjustingstructure 43 is carired'by breaker 10 and includes an adjusting mem ber44 to adjust the spring tension of spring 38 for increasing ordecreasing the amount of fiux in the relay 40 needed to pick ,uparmature 45. Moving with and carried by adjusting member 44 is a visualindicator 48 which maybe calibrated to indicate the pickup ratings ofarmature 45 or the amount of tension spring 38 is exerting on armature45 against pickup.

Armature 45 has mounted thereon an adjusting screw tripping hammer 50which initiates operation of tripping tion with indicator means 59 forindividual identification of tripped and nontripped phases. Each of the.collar 60 with a clearance.

phases is provided with indicator means 59 which utilizes a portion ofcommon indicator trip shaft 58 presented to that phase. Each indicatormeans 59 includes a collar 60 journaled in alignment with the collars ofthe other indicator means, which collars 60 may be journaled in a commonsupport, such as the breaker 10. Collar 60 also cooperates with thecollars of the other indicator means to journal indicator trip shaft 58.

Collar 68 presents walls 61 defining a recess 62 thereetween. Collar 69further has rigidly attached thereto an indicator 54 for rotationtherewith. Indicator 54 is provided with a latched portion 64 which, ina nontrip position, engages a latch 65 for holding latch portion 64 inthe nontripped position. Latch 65 includes a phase indicator trip bar'66mounted on breaker 10 and a phase indicator trip pin 67 mounted on phaseindicator trip bar 66. Means responsive to operation of trippingmechanism 41 of one of the breakers is provided for disengaging latch 65from latched portion 64 to drop indicator 54. These means are shown asrelay 40 and its armature 45. As'armature 45 closes, it engages phaseindicator trip pin 67 thereby disengaging pin 67 from latch portion 64and freeing the phase trip indicator 54. Phase trip indicator 54 rotatesclockwise by its own weight and is aided in that rotation by torsionalresilient means, shown as torsion spring 70. Fig. 5 of the drawingsshows the nontripped relay 40, and Fig. .6, the tripped positionthereof. Torsion spring 70'also maintains tension on collar 60 to biasthe latched portion 64 of indicator. 54 against latch 65.

A limit pin 71 is mounted on indicator trip shaft 58 adjacent collar65), and extends into recess 62 of Limit pin 71 cooperates with lostmotion with walls 61 of recess 62 to turn or rotate the shaft 58. Thelost motion with which limit pin 71 and walls 61 cooperate facilitateease of alignment and adjustment of pin 71 with each recess 62; Collar60 rotates upon release of phase trip indicator 54. Collar 60 rotates inresponse to the urging of walls 61 of recess 62 upon limit pin 71.

Means are provided for resetting indicator trip shaft 5.8 to therebyreset any of indicator means 59 from a tripped to a nontripped position.These means include a breaker tripped indicator reset button 74 (Figs. 1and 2) mounted in breaker 10 for indicating the tripped breaker bypopping out when overload conditions exist in the protectedinstallation. Button 74 may be pushed in toward the breaker 10 forresetting indicating means 59 by rotation of indicator trip shaft 58.Manual pressure is applied to button 74 and is translated into rotarymotion exerted on shaft 58 by links 75, 76 and 77.

Mounted on one end of indicator trip shaft 58 is a trip cam 80 which isaffixed to indicator trip shaft 58 for rotation therewith. Trip cam 84)is provided with a first end 81 and a second cammed end 82. A lockoutdevice or block 83 may be provided and mounted on the breaker trip shaft52 and aflixed thereto. On tripping of breaker 10 the first end 81 oftrip cam 80 engages lockout block 83 and prevents accidental reclosingof the breaker without resetting the indicator trip shaft .58. A spring86 is provided to effect positive lockout by exerting a positive torqueto hold indicator trip shaft 58 and the associated trip cam 80 in atripped position. Spring 86 also biases first end 81 of trip cam 80against lockout block 83 preventing rotation of block 83 and furtheraids in the clockwise rotation of indicator 54 and locking cam 80 in atripped position as a result of the toggle action of spring 86. Manualpressure applied to the reset button 74 is necessary to overcome theresilientforce and restore spring 86 to a nontrip position.

Resetting indicator trip shaft 58 from a tripped to a nontrippedposition, ,causes first end 81 of trip cam 81) to disengage itself fromlockout block 83. Lockout '5 block 83 is then free to be restored to itsnontripped position.

The second cammed end .82 of trip cam 80'engages an electrical switch 87which is carried by breaker and mounted adjacent trip cam 80. Thisswitch 87 is used to effect operation of desired audible, visual or thelike devices to additionally effect indication of a tripped phase.

Tripping mechanism 41 further includes a Y-shaped star wheel 93pivotally carried by breaker 10. A roller 94 is mounted on one of thelegs of the star wheel 93 and is in engagement with block 51. A triprocker 97, having a first and a second rocker arm 98, 99 is pivotallycarried by breaker 10 at a pivot 100. Pivotally mounted on first rockerarm 98 is a roller 102 which engages one of the legs of the star wheel93 in endwise engagement. The second rocker arm 99 has an outer surface103 eccentrically ground with its geometric center within the rocker 97but above its pivot 100. Therefore pressure exerted on the outer surface103 of the second rocker arm 99 will produce a clockwise turning torque(as viewed in Fig. l) on the rocker 97 about its pivot 100. A cam plate104 having an arcuate inner cam opening 105 is mounted on breaker 10 andis adjacent rocker 97. An operating arm 106 having a first end 107 and asecond end 108, has its first end 107 mounted adjacent cam plate 104.The first end 107 carries a pin 111 which projects through the cam plate104 at the inner end of cam opening 105. The pinlll has a roller 112journaled thereon which roller 112 is free to rotate but is firmly heldagainst axial movement by pin 111 and operating arm 106. The roller 112abuts and engages the outer surface 103 of the second rocker arm 99. Atrip latch 113 having a cam surface 121, is pivotally carried by theoperating arm 106 at its pin 111. The second end 108 mounts a pivotelement 115 for pivotally attaching an insulating arm 116 and a firstindicator link 119.

Operating arm 106 has a changing pivot point which shifts from a centerpoint 120 intermediate the ends 107, 108, when the contacts are opened,to a point coinciding with the pin 111 of the first end 107 when thecontacts are reclosed. A trip pin 114 is mounted on a trip latch bar 122and engages cam surface 121 of a trip latch 113. Trip latch bar 122 ispivotally mounted on a shaft 123. A cam rider 126 is carried by triplatch bar 122. A spring 127, biasing the trip latch bar 122 and its trippin 114 against cam surface 121 of trip latch 113, is connected at oneend thereof to breaker 10 and the other end thereof is connected to theoperating arm 106 intermediate the center point 120 and the second end108.

A manual reclosing mechanism 130 comprises a handle 131 mounted on ashaft 132 journaled in breaker 11 A reclosing cam 133 is aflixed toshaft 132 and rotates therewith upon rotation of handle 131. Handle 131is spring biased by a torsion spring 134 which returns the handle 131 toa normal reset position upon release. Cam rider 126 slidingly engagesclosing cam 133 when the breaker has tripped and the contacts are open.Reclosing is effected by rotating handle 131 whereupon the cam rider 126follows closing cam 133 to reset the trip pin 114 against cam surface121, thereby resetting trip latch bar 122.

Insulated arm 116, which is pivotally attached to the second end 108 ofoperating arm 106, is also pivotally attached at its opposite extremityto contact arm at pivot 135. First indicator link 119 is pivoted atpivot 137 and has a second indicator link 138 pivotally attached atpivot 139. The second indicator link 138 is attached to an open-closedbreaker indicator 140 pivotally mounted on pivot 141 carried by breaker10.

I The opening of breaker 10 (shown in Fig. 1 in a closed position) whichoperation is hereafter explained, occurs 6 when overload currents causethe single phase circuit it is protecting, to be interrupted.

As a prolonged overload current or a short circuit condition ispresented to breaker 10, trip coil 21 presents an, increased magneticflux to relay 40. This increased magnetic flux attracts armature 45 forpickup. However, armature 45 is restrained from pickup by spring 38.Therefore, when the overload current through trip coil 21 is greatenough, armature 45 will overcome the tension of spring 38 and pick up.

As the armature 45 approaches closing, it engages the phase indicatortrip pin 67 causing it to be dislodged from latch portion 64, therebydropping phase trip indicator 54 into tripped indicating position. Asphase trip indicator 54 drops, it rotates collar 60 clockwise by its ownweight and the added torsional force of spring 70. Rotation of collar 60causes walls 61 of recess 62 to traverse the lost motion and to engagelimit pin 71 which in turn rotates indicator trip shaft 58 a portion ofone revolution. Rotation of indicator trip shaft 58 is translated bylinks 75, 76 and 77 into horizontal popping-out of breaker trippedindicator reset button 74 indicating the tripped breaker.

Trip cam also rotates with rotation of indicator trip shaft 58, andengages lockout block 83 with its first end 81. Second cammed end 82engages electrical switch 87 to effect operation of desired audible,visual or like alarm devices. Spring 86 provides positive locking biasto hold trip cam 80 in the lockout or tripped position.

As closing of armature 45 is effected, it also causes tripping hammer 50of armature 45 to engage block 51 and cause block 51 to be rotatedcounterclockwise a portion of a revolution. The counterclockwiserotation of block 51 causes roller 94 of one of the legs of star wheel93 to transmit a clockwise rotation to the star wheel 93. As the starwheel 93 rotates clockwise, roller 102 mounted on first rocker arm 98,which roller 1112 endwise engages one of the legs of star wheel 93,drops from endwise engagement therewith freeing rocker arm 97 forclockwise rotation about its pivot 100. Roller 112 of operating arm 106exerts the forces of spring 127 and breaker contact springs 19, 29against outer surface 103 of rocker arm 97 and further causes a positiveclockwise rotation of rocker arm 97. Roller 112 of operating arm 106becomes disengaged from outer surface 103, thus permitting pin 111carried by the first end 107 of operating arm 106 to follow the camopening in cam plate 104. This movement of first end 107 of operatingarm 106 permits operating arm 106 to pivot about the center point 120.Trip latch 113 has its latched cam surface 121 released from the trippin 114, also freeing trip latch bar 122. The trip latch bar 122 rotatesclockwise about its pivot 123, being limited by a stop 160. This places.cam rider 126 in engagement with closing cam 133. The pivoting ofoperating arm 106, aided by the spring 127 and breaker contact springs19, 29, causes second end 108 to move counterclockwise to aid insulatedarm 116, which being attached also to the contact arm 20, draws thecontact arm 20 out of contact with the main finger 18. Breaking thecontact of contact arm 20 and main finger 18 transfers the current flowto arcing contacts 26, 27 which open after main finger 18 and contactarm 20. The are drawn in opening arcing contacts 26, 27 travels upwardtoward an arc chute 161 defined by notched barrier plates 162 and leavesthe arcing contacts 26, 27 to advance along arc runner 28 and an arcingjet 163 carried by arcing contact arm 20. Are chute 161, barrier plates162 and the addition of a magnetic iron core 164 adjacent the undersideof arc runner 28, in combination with the thermal and magneticconditions caused by the arc, all aid in its extinguishment.

At the same time insulating arm 116 is drawn back to open breaker 10,the first indicator link 119 pivots clockwise about pivot 137 whichcauses link 119 to act on second indicatorlink 138 to pivot theopen-closed breaker indicator 140 aboutpivot 141 indicating the opencondition of the contacts of breaker 10.

A clockwise rotation of handle 131 of manual reclosing mechanism 130after pushing the phase trip indicator reset button 74, will restorebreaker to a closed position.

Although but one embodiment has been illustrated and described it willbe apparent to those skilled in the art that various changes andmodifications may be made therein without departing from the spirit ofthe invention or from the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. In a multiphase protected installation in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting a circuit and a tripping mechanismadapted to make and break said contacts; the combination of an indicatortrip shaft with indicator means for visually identifying a tripped and anontripped phase, each said indicator means comprising a collarjournaled in alignment with the collars of the other said indicatormeans and cooperating with the collars of the other said indicator meansfor journaling said trip shaft, said collar having a recess, anindicator rigidly attached to said collar for rotation therewith, saidindicator being provided with a latched portion, a latch for holdingsaid latched portion in a nontrip position, means responsive tooperation of said tripping mechanism of one of said breakers fordisengaging said latch from said latched portion to drop said indicator,a limit pin mounted on said shaft and extending into said recess of saidcollar for turning said shaft in response to engagement of the Wall ofsaid recess with said pin, torsional reilient means for maintainingtorsional tension on said collar; and means for resetting said shaft tothereby reset any of said indicator means from a tripped to a nontrippedposition.

2. In a multiphase protected installation in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting a circuit and a tripping mechanismadapted to make and break said contacts; the combination of an indiactortrip shaft with indicator means for visually identifying a tripped and anontripped phase, each said indicator means comprising a collarjournaled in alignment with the collars of the other said indicatormeans and cooperating with the collars of the other said indicator meansfor journaling said trip shaft, said collar having a recess, anindicator rigidly attached to said collar for rotation therewith, saidindicator being provided with a latched portion, a latch for holdingsaid latched portion in a nontrip position, means responsive tooperation of said tripping mechanism of one of said breakers fordisengaging said latch from said latched portion to drop said indicator,a limit pin mounted on said shaft and extending into said recess of saidcollar with a clearance for turning said shaft with lost motion inresponse to engagement of the wall of said recess with said pin,torsional resilient means for maintaining torsional tension on saidcollar; and means for resetting said shaft to thereby reset any of saidindicator means from atripped to a nontripped position.

3. In a multiphase protected installition in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting a circuit and a tripping mechanismadapted to make and break said contacts; the combination of an indicatortrip shaft with indicator means for visually identifying a tripped and anontripped phase, each said indicator means comprising a collarjournaled in alignment with the collar of the other said indicator meansin a common support and cooperating with the collars of the other saidindicator means for journaling said trip shaft, said collarhaving arecess, an indicator rigidly attached to said collar for rotationtherewith, 'said'indicator being-providedwith a'latched portion, a latchfor holding said latched portion in a nontrip position, means responsiveto operation of said tripping mechanism of one of said breakers fordisengaging said latch from said latched portion to drop said indicator,a limit pin mounted on said shaft and extending into said recess of saidcollar with a clearance for turning said shaft with lost motion inresponse to engagement of the wall of said recess with said pin,torsional resilient means for maintaining torsional tension on saidcollar; means for resetting said shaft to thereby reset any of saidindicator means from a tripped to a nontripped position; a trip cammounted on said shaft for rotation therewith and an electrical switchmounted on said breaker adjacent said trip cam, said trip cam engagingsaid switch for actuation thereof in response to rotation of said shaft.

4. In a multiphase protected installation in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting a circuit and a tripping mechanismadapted to make and break said contacts; the combination of an indicatortrip shaft with indicator means for visually identifying a tripped and anontripped phase, each said indicator means comprising a collarjournaled in alignment with the collar of the other said indicator meansin a common support and cooperating with the collars of the other saidindicator means for journaling said trip shaft, said collar having arecess, an indicator rigidly attached to said collar for rotationtherewith, said indicator being provided with a latched portion, a latchfor holding said latched portion in a nontrip position, means responsiveto operation of said tripping mechanism of one of said breakers fordisengaging said latch from said latched portion to drop said indicator,a limit pin mounted on said shaft and extending into said recess of saidcollar with a clearance for turning said shaft with lost motion inresponse to engagement of the wall of said recess with said pin,tortional resilient means for maintaining torsional tension on saidcollar; a lockout block presented by said tripping mechanism, a trip cammounted on and rotating with said shaft for locking said lockout blockin a tripped position, and means for resetting said shaft and said tripcam to thereby reset any of said indicator means and to reset saidlockout block from a tripped to a nontripped position.

5. In a multiphase protected installation in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting a circuit and a tripping mechanismadapted to make and break said contacts; the combination of an indicatortrip shaft with indicator means for visually identifying a tripped and anontripped phase, each said indicator means coniprising a collarjournaled in alignment with the collars of the other said indicatormeans in a common support and cooperating with the collars of the othersaid indicator means for journaling said trip shaft, said collar havinga recess, an indicator rigidly attached to said collar for rotationtherewith, said indicator being provided with a latched portion, a latchfor holding said latched portion in a nontrip position, means responsiveto operation of said tripping mechanism of one of said breakers fordisengaging said latch from said latched portion to drop said indicator,a limit pin mounted on said shaft and extend ing into said recess ofsaid collar with a clearance for turning said shaft with lost motion inresponse to engagement of the wall of said recess with said pin,torsional resilient means for maintaining torsional tension on saidcollar; a trip cam, an electrical switch mounted on said breakeradjacent said trip cam, a lockout block presented by said trippingmechanism, said trip cam being mounted on and rotating with said shaft,said trip cam upon rot tion of said shaft simultaneously engages saidswitch for actuation thereof and locks said lockout block in a trippedposition, and means for resetting said shaft and said trip cam tothereby reset any of said indicator'rneans and to reset said switch andsaid lockout block from a tripped to a nontripped position, saidindicator means providing visual indication of the tripped andnontripped condition of said breaker.

6. In a multiphase protected installation in which each phase isprovided with a circuit breaker, each circuit breaker having make andbreak contacts for interrupting circuit and a tripping mechanism adaptedto make and break said contacts; the combination of a trip shaft with indicator means for visually identifying a tripped and a nontripped phase,each said indicator means comprising a collar journaled in alignmentwith the collars of the other said indicator means in a common supportand cooperating with the collars of the other said indicator means forjournaling said trip shaft, said collar having a recess, an indicatorrigidly attached to said collar for rotation therewith, said indicatorbeing provided with a latched portion, a latch for holding said latchedporton in a nontrip position, means responsive to operation of: saidtripping mechanism of one of said breakers for disengaging said latchfrom said latch portion to drop said indicator, a limit pin mounted onsaid shaft and extending into said recess of said collar with aclearance for turning said shaft with lost motion in response toengagement of the wall of said recess with said pin, torsional resilientmeans for maintaining torsional tension on said collar; a trip earn, anelectrical switch mounted on said breaker adjacent said trip earn, alockout block presented by said tripping mechanism, said trip cam beingmounted on and rotating with said shaft, said cam being adapted toeffect simultaneous operation of said switch and of said lockout blockin a tripped position upon rotation of said shaft, resilient meanscarried by said breaker and said trip cam for positive biasing of saidtrip cam holding it in a tripped position, and means for resetting saidshaft and said trip cam to thereby reset any of said indicator means andto reset said switch, said lockout block and said resilient means from atripped to a nontripped position.

References Cited in the file of this patent UNITED STATES PATENTS1,480,306 Scott Jan. 8, 1924

